title: Contact lens care solutions downregulate membrane-associated mucins 1 and 16 in cultured human corneal epithelial cells and at the rat corneal surface in vivo.
abstract: OBJECTIVE
  The purpose of this study was first to evaluate the effect of multipurpose contact lens care solutions (MPSs) on the expression of membrane-associated mucins (MUC1 and MUC16) in SV40-transformed human corneal epithelial (HCE-T) cells and in vivo rat cornea. The second aim of this study was to determine the role of the common MPS additive boric acid in reducing mucin expression and release.
  
  
  METHODS
  The HCE-T cells were exposed to different concentrations of MPS-F, MPS-G, MPS-H, MPS-I, and MPS-J with 100% treatment for 30 minutes and 10% treatment for 24 hours. MUC1 and MUC16 expressions were subsequently analyzed by Western blotting. Wister rats were also subjected to MPS-A, MPS-B, MPS-C, MPS-D, and MPS-E and received phosphate-buffered saline exposure (1 drop in the right eye every 10 minutes for 1 hour). The left eye was used as control. Cornea sections and lysates were used for the immunohistochemical assay of MUC1 and MUC16 expressions. Conditioned media from treated HCE-T cells were also analyzed using Western blotting.
  
  
  RESULTS
  The MPSs containing boric acid downregulated MUC1 and MUC16 in the rat cornea, whereas MPSs without boric acid had no effect as demonstrated by the Western blotting and immunohistochemical analysis. Conditioned media from MPS-containing boric acid revealed some trace of MUC16.
  
  
  CONCLUSIONS
  The clinical use of MPSs containing boric acid that reduce MUC1 and MUC16 availability should be avoided. Additionally, the presence of MUC16 in the conditioned media suggests that boric acid may have enhanced cleavage of MUC16 at the cell membrane surface.
authors.affiliation: Central Research Laboratory (K.T., M.I.), Menicon Co, Ltd, Kasugai, Japan; Department of Ophthalmology (Y.H.), Toho University Sakura Medical Center, Sakura, Japan; and Department of Ophthalmology (H.D.C.), University of Texas Southwestern Medical Center, Dallas, TX.
authors.forename: Kissaou
authors.initials: K
authors.lastname: Tchedre
authors.forename: Masaki
authors.initials: M
authors.lastname: Imayasu
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hori
authors.forename: H Dwight
authors.initials: HD
authors.lastname: Cavanagh
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D001888:Boric Acids / Q000494:pharmacology; D018394:CA-125 Antigen / Q000187:drug effects* / Q000378:metabolism; D002478:Cells, Cultured; D018639:Contact Lens Solutions / Q000494:pharmacology*; D003315:Cornea / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D019573:Epithelium, Corneal / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000187:drug effects* / Q000378:metabolism; D018396:Mucin-1 / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D001888:Boric Acids; D018394:CA-125 Antigen; D018639:Contact Lens Solutions; C451759:MUC16 protein, human; D008565:Membrane Proteins; D018396:Mucin-1; C032688:boric acid